1. Field of the Invention
The present invention relates to a flow channel system of a vacuum cleaner, in particular to an air circulation type vacuum cleaner which is capable of doubling suction force besides suction force of a suction fan by circulating discharged air to the suction side again and inducing vacuum pressure on the suction side.
2. Description of the Prior Art
In the general vacuum cleaner, an one-direction suction method for sucking dusts by using only suction force generated by a suction fan is mainly used, in this case because a bottom surface of a suction blower is adsorbed to a surface to be cleaned, suction ability of the vacuum cleaner lowers a lot. In the consideration of the problem, an air circulation method (Re: Japan patent official bulletin No. 31-62814) is represented, the method refluxes part of the air wind generated by the suction fan to the suction blower again, jets it with a certain pressure, and sucks the dusts while blowing the dusts.
As described above, in the air circulation method, because the air wind circulated from the suction fan has to blow the dusts on the bottom surface to be cleaned with a certain discharge pressure and suck the dusts with a certain suction pressure, the air circulation type vacuum cleaner has a problem to control discharge pressure of circulation air and suction pressure of the suction fan. In addition, because sectional area of the suction blower lengthens by expanding the reflux flow channel of the air from the discharge side of the blow fan to the suction blower, the conventional air circulation type vacuum cleaner has a problem to clean narrow place. Therefore, the conventional one-directional suction type vacuum cleaner is used in general.
FIG.1 is a schematic view illustrating a flow channel system of the conventional one-bodied vacuum cleaner adapting the one-directional suction method.
As depicted in FIG.1, the conventional one-directional suction type one-bodied vacuum cleaner comprises a casing 1 having a suction port (no reference numeral) and an exhaust port (no reference numeral) on the both upper and lower ends, a suction blower 2 placed so as to be consecutive to the suction port side inside of the casing 1 in order to suck impurities with surrounding air, a dust collect filter 3 placed so as to be consecutive to an outlet side of the suction blower 2 in order to filter the impurities included in the sucked air, a suction fan 4 placed so as to be consecutive to the outlet side of the dust collect filter 4 in order to generate the suction force, and a fan motor 5 placed so as to be consecutive to the discharge side of the suction fan 4 in order to generate the operating force for rotating the suction fan 4.
The suction blower 2 is formed as a frustum conical shape getting narrower toward the outlet. The dust collect filter 3 is formed so as to make its crosssectional area include the outlet side of the suction blower 2, and the suction fan 4 is a centrifugal fan having a diffuser used in general in the vacuum cleaner.
In the flow channel system of the conventional one-bodied vacuum cleaner, the suction fan 4 generates the suction force while rotating by the operation of the fan motor 5, the suction force is transmitted to the inlet side of the suction blower 2 after passing through the dust collect filter 3, and sucks the impurities on the place to be cleaned with the air.
After that, the air sucked to the suction blower 2 passes the dust collect filter 3 consecutively placed to the suction blower 2, during the process the impurities are left by being filtered by the dust collect filter 3, the air directly passes the dust collect filter 3, is sucked to the inlet side of the suction fan 4, is discharged through the diffuser (not shown), cools the fan motor 5 consecutively placed to the discharge side of the suction fan 4, and is discharged to the outside of the vacuum cleaner through a ventilation hole (not shown) of the casing 1 placed on the rear side of the fan motor 5.
However, in the structure of the flow system of the conventional one-bodied vacuum cleaner, the air and impurities are sucked together by the suction force of the suction fan 4 transmitted to the inlet side of the suction blower 2 by the operation of the fan motor 5, when the suction force generated from the suction fan 4 is small, the ability of the vacuum cleaner lowers, in the consideration of it when the suction force increases by increasing the capacity of the fan motor 5, the power consumption increases and the discharge noise in proportion to the rotating speed of the suction fan 4 increases together.
In order to solve above-mentioned problem of a flow channel system of the conventional one-bodied vacuum cleaner, the object of the present invention is to provide a vacuum cleaner which is capable of doubling suction force for sucking impurities with dusts while keeping capacity of a fan motor as same.
In order to achieve the object of the present invention, the air circulation type vacuum cleaner according to the present invention comprises a casing having a suction port and an exhaust port separately, a suction blower placed so as to be consecutive to the suction port of the casing in order to suck impurities with surrounding air, a suction fan having a dust collect filter placed so as to be consecutive to the outlet side of the suction blower in order to filter the impurities from the sucked air and a fan motor for generating suction force, at least one reflux pipe arranged its inlet portion is placed on the discharge side of the suction fan having the fan motor in order to return the discharge air discharged from the suction fan to the suction side, and at least one ejector installed on the outlet side of the reflux pipe in order to jet the discharge air with high speed.